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AUS-8 and conventional D2 offer a familiar choice: more stainless corrosion resistance and toughness, or more abrasive edge retention. AUS-8 leads the first two properties in Larrin Thomas’s ratings, while D2 leads wear resistance. That makes D2 a tradeoff, not an automatic upgrade.
Performance Ratings
For the science, we turn to Dr. Larrin Thomas of Knife Steel Nerds, who has kindly allowed us to share his ratings here.
| Property | AUS-8 | D2 |
|---|---|---|
| Abrasive edge retention | ||
| Toughness | ||
| Corrosion resistance |
Heat treatment, hardness and geometry affect actual knives.
D2 for Abrasive Slicing
D2 rates 5 for abrasive edge retention, compared with AUS-8 at 3. We would favor D2 for repeated abrasive cuts when the knives otherwise match your needs.
Check that the listing means conventional D2. CPM D2 is a separate version, and the CPM designation should not be silently added to an unspecified D2 knife.
Our AUS-8 steel profile takes a closer look at its properties and care.
AUS-8 Offers More Toughness
AUS-8 rates 6 for toughness against D2 at 3.5. For a user more concerned about edge damage than gradual dulling, AUS-8’s position is worth considering even if D2 sounds like the more desirable name.
That toughness advantage does not make a thin folding knife a good tool for twisting or prying. Steel ratings help compare materials; they do not replace the limits of the design.
Our D2 steel profile takes a closer look at its properties and care.
AUS-8 Is the Easier Rust-Care Choice
AUS-8 rates 7 for corrosion resistance and D2 4.5. AUS-8 is stainless; D2 requires more attention to damp or corrosive exposure. For routine carry in humid conditions, we would give AUS-8 the nod on this property.
Both benefit from cleaning and drying. If rust care is your biggest concern, do not let D2’s wear advantage distract from the maintenance tradeoff.
Which Is the Better Everyday Purchase?
We would take D2 for abrasive slicing and AUS-8 when toughness and stainless care are more useful. A well-designed AUS-8 knife can be a better everyday choice than a D2 knife with a less useful grind or handle.
The ratings alone do not tell you which knife offers better value. Compare the actual models and prices, and avoid paying for a steel name without a clear specification.
Composition
Our steel composition guide explains the elements and the differences between reported values, ranges and limits.
AUS-8: Spyderco knife-maker-reported composition: ranges and single reported values, not a producer batch certificate. Single figures are reproduced as listed; the source does not identify whether each is a typical value or a limit. Spyderco: steel chart.
D2: Niagara typical composition, mass %; selected elements, not a batch analysis. Niagara Specialty Metals: D2.
| Element | AUS-8 | D2 |
|---|---|---|
| Carbon (C) | 0.7–0.75% | 1.42% |
| Chromium (Cr) | 13–14.5% | 11.5% |
| Molybdenum (Mo) | 0.1–0.3% | 0.9% |
| Vanadium (V) | 0.1–0.26% | 0.8% |
| Nickel (Ni) | 0.49% | Not listed |
| Manganese (Mn) | 0.5% | Not listed |
| Silicon (Si) | 1% | Not listed |
| Phosphorus (P) | 0.04% | Not listed |
| Sulfur (S) | 0.03% | Not listed |
Compare Two Knife Steels
Sources and Update Notes
- Dr. Larrin Thomas: knife steel ratings · Property ratings; the scores describe steels rather than individual finished knives.
- Spyderco: 2026 Steel Chart
- Niagara Specialty Metals: D2
